The modern communications era has brought about a tremendous expansion of wireline and wireless networks. Computer networks, television networks, and telephony networks are experiencing an unprecedented technological expansion, fueled by consumer demand. Wireless and mobile networking technologies have addressed related consumer demands, while providing more flexibility and immediacy of information transfer.
Current and future networking technologies continue to facilitate ease of information transfer and convenience to users. In order to provide easier or faster information transfer and convenience, telecommunication industry service providers are developing improvements to existing networks. For example, the evolved universal mobile telecommunications system (UMTS) terrestrial radio access network (E-UTRAN) is currently being developed. The E-UTRAN, which is also known as Long Term Evolution (LTE), is aimed at upgrading prior technologies by improving efficiency, lowering costs, improving services, making use of new spectrum opportunities, and providing better integration with other open standards.
However, coverage by these new networking technologies, which may comprise packet switched (PS) networks (e.g., an Internet Protocol (IP) Multimedia Subsystem (IMS) capable network), may not be universal as they are deployed. Moreover, as these new PS networks are deployed, they may not initially support all modes of communication. For example, upon initial deployment of a PS network, full IMS support for voice over IP (VoIP) may not be provided by the PS network and accordingly the PS network may not support a voice call. Accordingly, a mobile terminal connected to a PS network may not be able to engage in a voice call unless transferred to a legacy circuit switched (CS) network configured to support voice calls. Some PS networks implement procedures referred to as circuit switched fallback (CSFB), wherein the PS network is configured to handover a mobile terminal to a network capable of supporting CS connections when the mobile terminal is an end point for a communication requiring a CS connection.
However, not all PS networks support CSFB and accordingly, a mobile terminal connected to a PS network that does not support CSFB may not be able to engage in a communication, such as a voice call, that may require a CS connection.